Claims that liberal bias keeps conservatives off college faculties almost always focus on the humanities and social sciences, where judgments about what constitutes good scholarship can seem subjective to an outsider. But studies that find registered Republicans in the minority at elite universities show that Republicans are almost as rare in hard sciences like physics and in engineering departments as in softer fields. Why?

One answer is self-selection – the same sort of self-selection that leads Republicans to outnumber Democrats four to one in the military. The sort of person who prefers an academic career to the private sector is likely to be somewhat more liberal than average, even in engineering.

But there's also, crucially, a values issue. In the 1970's, even Democrats like Daniel Patrick Moynihan conceded that the Republican Party was the “party of ideas.” Today, even Republicans like Representative Chris Shays concede that it has become the “party of theocracy.”

Consider the statements of Dennis Baxley, a Florida legislator who has sponsored a bill that – like similar bills introduced in almost a dozen states – would give students who think that their conservative views aren't respected the right to sue their professors. Mr. Baxley says that he is taking on “leftists” struggling against “mainstream society,” professors who act as “dictators” and turn the classroom into a “totalitarian niche.” His prime example of academic totalitarianism? When professors say that evolution is a fact.